We are traveling with a linux based computer (I'm really rethinking that choice at the moment), and have two new sony ebook 505s that we were planning on using for reading material. I understand that I can't download from the sony store on a linux machine, but I also just found out that I can't check e-books out from my public library to read on the 505 unless I am running the sony software.

My question is: can I download the sony software to a memory stick, plug said memory stick into a machine running windows in an internet cafe, and get books that way?

Calibre runs just fine under linux. There are tons of free book sources out there, and paid-for book sources other than the Sony store. Given the DRM and authorization process, not to mention that you need to run an installer, I would say your plan will only work in an internet cafe where visitor PCs run with local admin rights. Which would be terminally stupid of them.

We are traveling with a linux based computer (I'm really rethinking that choice at the moment), and have two new sony ebook 505s that we were planning on using for reading material. I understand that I can't download from the sony store on a linux machine, but I also just found out that I can't check e-books out from my public library to read on the 505 unless I am running the sony software.

Once the device is authorized (you need to do it only once with Digital Editions), you should be able to just copy the books to the USB mass storage drive. I'm not sure how your library handles the check out process, but as long as you get simple PDF or EPUB files, you should be good to go.

My question is: can I download the sony software to a memory stick, plug said memory stick into a machine running windows in an internet cafe, and get books that way?

I think what you really need is Adobe Digital Editions with an Adobe ID that includes your PRS-505's. ADE is a small download on a new Windows or Mac computer, but then this becomes one of your 6 allowed devices. I don't know if there is a way to get ADE to work from a memory stick.

If you stay with the Linux netbook, your best bet might be to buy MOBI or eReader ebooks and strip their DRM because these formats only require a web browser to buy (MOBI needs a PID, e.g. from a Windows PC, but can then be downloaded to any computer). Once DRM-free, Calibre can format shift the ebooks for the Sony.